1. Technical Field
The present invention relates to an electronic timepiece with an internal antenna.
2. Related Art
Japanese Unexamined Patent Appl. Pub. JP-A-2011-021929 discloses a GPS (Global Positioning System) wristwatch 1 that has an annular antenna 11 and a round solar panel support substrate 120 disposed directly below the antenna 11. As shown in FIG. 4 of JP-A-2011-021929, the antenna 11 has an annular dielectric substrate 111, and a conductive antenna electrode 112 (including an antenna body 113, coupling part 114, and feed part 115) formed on the surface of the dielectric substrate 111. The solar panel support substrate 120 is a conductive substrate that supports the dial 2 and solar panel 120A, and functions as a ground plane connected to a connection terminal of a circuit board 25.
The wristwatch 1 disclosed in JP-A-2011-021929 causes the annular antenna body 113 formed on the surface of the dielectric substrate 111 and the solar panel support substrate 120 (ground plane) to resonate, and receives signals from GPS satellites. Because the induced EMF increases as the magnetic flux passing through the plane of the loop increases, the reception performance of the loop antenna increases. However, because the open part of the annular dielectric substrate 111 is blocked directly below the dielectric substrate 111 by the round solar panel support substrate 120 connected to the ground terminal, little magnetic flux passes through the loop plane and the reception performance of the antenna is reduced.